{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T11:13:36Z","timestamp":1782386016392,"version":"3.54.5"},"reference-count":50,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2019,9,9]],"date-time":"2019-09-09T00:00:00Z","timestamp":1567987200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2018R1A5A7025522"],"award-info":[{"award-number":["2018R1A5A7025522"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2019R1F1A1062162"],"award-info":[{"award-number":["2019R1F1A1062162"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>With the development of wearable devices, strain sensors have attracted large interest for the detection of human motion, movement, and breathing. Various strain sensors consisting of stretchable conductive materials have been investigated based on resistance and capacitance differences according to the strain. However, this method requires multiple electrodes for multipoint detection. We propose a strain sensor capable of multipoint detection with a single electrode, based on the ultrasound pulse\u2013echo method. It consists of several transmitters of carbon nanotubes (CNTs) and a single polyvinylidene fluoride receiver. The strain sensor was fabricated using CNTs embedded in stretchable polydimethylsiloxane. The received data are characterized by the different times of transmission from the CNTs of each point depending on the strain, i.e., the sensor can detect the positions of the CNTs. This study demonstrates the application of the multipoint strain sensor with a single electrode for measurements up to a strain of 30% (interval of 1%). We considered the optical and acoustic energy losses in the sensor design. In addition, to evaluate the utility of the sensor, finger bending with three-point CNTs and flexible phantom bending with six-point CNTs for the identification of an S-curve having mixed expansion and compression components were carried out.<\/jats:p>","DOI":"10.3390\/s19183877","type":"journal-article","created":{"date-parts":[[2019,9,9]],"date-time":"2019-09-09T04:12:40Z","timestamp":1568002360000},"page":"3877","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Multipoint-Detection Strain Sensor with a Single Electrode Using Optical Ultrasound Generated by Carbon Nanotubes"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8565-7823","authenticated-orcid":false,"given":"Won Young","family":"Choi","sequence":"first","affiliation":[{"name":"Department of Mechanical Convergence Engineering, Hanyang University, Seoul 04763, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyeong Geun","family":"Jo","sequence":"additional","affiliation":[{"name":"Department of Mechanical Convergence Engineering, Hanyang University, Seoul 04763, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Soo Won","family":"Kwon","sequence":"additional","affiliation":[{"name":"Department of Mechanical Convergence Engineering, Hanyang University, Seoul 04763, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0854-0266","authenticated-orcid":false,"given":"Young Hun","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Mechanical Convergence Engineering, Hanyang University, Seoul 04763, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joo Young","family":"Pyun","sequence":"additional","affiliation":[{"name":"Department of Mechanical Convergence Engineering, Hanyang University, Seoul 04763, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5117-5853","authenticated-orcid":false,"given":"Kwan Kyu","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Mechanical Convergence Engineering, Hanyang University, Seoul 04763, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,9]]},"reference":[{"key":"ref_1","first-page":"266","article-title":"Strain sensing fabric for hand posture and gesture monitoring","volume":"108","author":"Lorussi","year":"2004","journal-title":"Stud. 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